The following invention relates to a printhead assembly having a flexible ink channel extrusion for an ink jet printer.
More particularly though not exclusively the invention relates to a printhead assembly having a flexible ink channel extrusion for an A4 pagewidth drop on demand printhead capable of printing up to 1600 dpi photographic quality at up to 160 pages per minute.
The overall design of a printer in which the ink channel extrusion can be utilized revolves around the use of replaceable printhead modules in an array approximately 8xc2xd inches (21 cm) long. An advantage of such a system is the ability to easily remove and replace any defective modules in a printhead array. This would eliminate having to scrap an entire printhead if only one chip is defective.
A printhead module in such a printer can be comprised of a xe2x80x9cMemjetxe2x80x9d chip, being a chip having mounted thereon a vast number of thermo-actuators in micro-mechanics and micro-electromechanical systems (MEMS). Such actuators might be those as disclosed in U.S. Pat. No. 6,044,646 to the present applicant, however, might be other MEMS print chips.
In a typical embodiment, eleven xe2x80x9cMemjetxe2x80x9d tiles can butt together in a metal channel to form a complete 8xc2xd inch printhead assembly.
The printhead, being the environment within which the ink channel of the present invention is to be situated, might typically have six ink chambers and be capable of printing four color process (CMYK) as well as infra-red ink and fixative. An air pump would supply filtered air through a seventh chamber to the printhead, which could be used to keep foreign particles away from its ink nozzles.
Each printhead module receives ink via an elastomeric extrusion that transfers the ink. Typically, the printhead assembly is suitable for printing A4 paper without the need for scanning movement of the printhead across the paper width.
The printheads themselves are modular, so printhead arrays can be configured to form printheads of arbitrary width.
Additionally, a second printhead assembly can be mounted on the opposite side of a paper feed path to enable double-sided high speed printing.
It is the object of the present invention to provide a printhead assembly having a flexible ink channel extrusion for delivery of ink and preferably air to an array of printhead modules situated along a printhead assembly. It is a further object of the present invention to provide a flexible ink channel extrusion for delivery of ink and preferably air to an array of printhead modules secured within an elongate channel of a printhead assembly.
The present invention provides a printhead assembly for a pagewidth drop on demand ink jet printer, comprising:
an array of printhead modules extending substantially across said pagewidth, and
an ink delivery extrusion substantially coextensive with said array of printhead modules, the extrusion having a plurality of ink channels for conveying discrete inks and a pattern of holes in a surface of the extrusion via which said discrete inks in said channels can pass from the extrusion to each said printhead module.
Preferably said ink delivery extrusion also includes an air channel for the delivery of air to the printhead modules.
Preferably said ink delivery extrusion is bonded onto a flexible printed circuit board.
Preferably an end of the ink delivery extrusion has a molded end cap fitted thereto, the end cap having a number of connectors to which ink and air delivery hoses can be connected.
Preferably each printhead module has a number of inlets having annular rings to seal against said surface of the ink delivery extrusion.
Preferably said ink extrusion is non-hydrophobic.
Preferably said holes in said surface of the extrusion are laser ablated.
Preferably said end cap has a spine including a row of plugs that are received within ends of the respective flow channels.
Preferably said end cap clamps onto the ink delivery extrusion by way of snap engagement tabs formed thereon.
Preferably said end cap includes connectors which interface directly with an ink cartridge.
As used herein, the term xe2x80x9cinkxe2x80x9d is intended to mean any fluid which flows through the printhead to be delivered to print media. The fluid may be one of many different colored inks, infra-red ink, a fixative or the like.